The Cozzarelli Prize recognizes six outstanding papers in the Proceedings of the National Academy of Sciences in the major scientific disciplines covered by that journal.

Petigura, Howard and University of California, Berkeley professor Geoffrey Marcy statistically determined that twenty percent of sun-like stars in our galaxy have Earth-size planets with surface temperatures that could support liquid water. The findings, gleaned from data collected from NASA’s Kepler spacecraft and the W. M. Keck Observatory, satisfied Kepler’s primary mission: a determination of the fraction of stars in our galaxy with potentially habitable planets.

“What this means is, when you look up at the thousands of stars in the night sky, the nearest sun-like star with an Earth-size planet in its habitable zone is probably only 12 light-years away and can be seen with the naked eye. That is amazing,” said Petigura, who led the analysis of the Kepler and Keck Observatory data.